shocks

How often should you replace your shocks?

Just a curiosity, friend of mine has an older Freightliner and over the weekend I noticed he had a shock that was seeping some oil from the seal that had ran down the side and started to collect dirt. My bringing this to his attention sparked a debate. Is that an out of service violation or...

Liking shocks,what this means???

Hi, I'm trying to replace front shocks on my truck. Looking at the photo, do I just have to remove two bolts that is holding them and it comes off? Or there's much more involved to it?? I'm just worried when I remove old shock, truck frame might twist or something, if I don't put a jack...